1. Field
The following description relates to multiple multicast technology. The following description also relates to a multiple multicast network system and method for ensuring transmission efficiency and transmission reliability in such a network.
2. Description of Related Art
Multicast refers to a scheme of simultaneously transmitting the same information in the form of image data, audio data, and related media data to at least two different receivers. For example, multicast may be used to distribute information from a sender to receivers for applications such as a video conference and an e-mail in the Internet, Multicast differs from unicast in that unicast is used to transmit a data packet only to a single predetermined receiver.
In the unicast, a data packet is repeatedly transmitted the same number of times as a number of receivers. The repeated transmission may lead to a reduction in an efficiency of a communication network. For example, the repeated transmission may cause a large transmission-related burden on a transmitter. However, an interactive Internet function, for example a video conference that occurs in real-time between multiple participants, may require real-time transmission of image and audio data from a sender. Accordingly, a multicast scheme for enabling data to be simultaneously exchanged among a plurality of users facilitates such communication.
In an example in which information is to be transmitted to 80 destination terminals from among 100 potential destination terminals, when a unicast scheme is used, the information is transmitted 80 times, once for each receiver. In this example, when a broadcast scheme is used and the information is transmitted to all potential receivers, and the information may be transferred to unnecessary 20 terminals. However, when a multicast scheme is used, the information may be transmitted to only the relevant 80 terminals.
Hence, unicast and broadcast schemes may result in certain inefficiencies when sharing information between parties across the Internet, including in real-time communications situations.